This invention is a manual circular calculator for determining an appropriate insulin injection dosage to be taken with a meal. Preferably, the calculator has a pair of circular members which rotate around a single common center to allow calculation of the dosage. The front member includes a viewing panel showing an array of insulin injection dosage values which are printed on the rear circular member. The front member includes a series of measured blood glucose levels along a radius adjacent the viewing panel. The rear member typically has visible ingested carbohydrate values positioned along the outer perimeter of the member and, as noted above, a number of insulin injection dosage value arrays which become visible as one member is turned relative to the other. It is common that a physician would have a kit of these inventive devices, so that the appropriate one could be chosen depending on the insulin sensitivity, age, and size of the patient. In using the inventive calculator, a patient measures his or her blood glucose level and determines the weight of carbohydrates to be ingested at a particular meal. The carbohydrate ingestion is found on the outer periameter of the back member of the device, the front member of the inventive device is turned so that an array of insulin values is visible, and the appropriate blood glucose level is read along the radius of the front circular member. The corresponding insulin injection dosage is seen in the window.
The American Diabetes Association reports that nearly six percent (6%) of the population in the United States, a group of about 16 million people, has diabetes. A significant number of these people do not know they have the disease. The Association further reports that diabetes is the seventh leading cause of death in the United States, contributing to nearly two hundred thousand deaths per year.
Diabetes is a chronic disease having no known cure. The complications of the disease include blindness, kidney disease, nerve disease, and heart disease, perhaps with stroke. Diabetes is said to be the leading cause of new cases of blindness in individuals between the ages of twenty and seventy-four. Perhaps twelve to twenty-four thousand people per year lose their sight because of diabetes. Diabetes is the leading cause of end-stage renal disease, accounting for nearly forty percent of new cases. Nearly sixty to seventy percent of those with diabetes have mild to severe forms of diabetic nerve damage which, in severe forms, can lead to lower limb amputations. People with diabetes are two-to-four times more likely to have heart disease and to suffer strokes.
Diabetes is a disease in which the body does not produce or properly use insulin, a hormone needed to convert sugar, starches, and the like into energy. Although the cause of diabetes is not completely understood, genetics, environmental factors, and viral causes have been partially identified.
There are two major types of Diabetes: Type I and Type II. Type I diabetes (formerly known as Juvenile Diabetes), is an autoimmune disease in which the body does not produce enough insulin and most often occurs in young adults and children. People with Type I diabetes must take daily insulin injections to stay alive.
Type II diabetes is a metabolic disorder resulting from the body""s inability to make enough, or properly to use, insulin. Type II diabetes accounts for ninety to ninety-five percent of diabetes. In the United States, Type II diabetes is nearing epidemic proportions, principally due to the increased number of older Americans and a greater prevalence of obesity and a sedentary life style.
Insulin, in simple terms, is the hormone that unlocks the cells of the body, allowing glucose to enter those cells and to feed them. Since, in diabetics, glucose cannot enter the cells, the glucose builds up in the blood and the body""s cells literally starve to death. Diabetics having Type I diabetes typically are required to self-administer insulin using, e.g., a syringe or a pen device with needle and cartridge. Continuous subcutaneous insulin infusion via implanted pumps is also available. Insulin typically is made chemically identical to human insulin by recombinant DNA technology. Although there are a variety of different insulins for rapid-, short-, intermediate-, and long-acting forms that may be used variously, separately or mixed in the same syringe, the use of insulin for treatment for diabetes is not to be ignored.
It is highly recommended by the medical profession that insulin-using patients practice self-monitoring of blood glucose (SMBG). Based upon the level of glucose in the blood, individuals may make insulin dosage adjustments before injection., Adjustments are necessary since blood glucose levels vary day-to-day for a variety of reasons, e.g., exercise, stress, rates of food consumption, types of food, hormonal changes (pregnancy, puberty, etc.) and the like. Despite the importance of SMBG, several studies have found that the proportion of individuals who self-monitor at least one a day significantly declines with age. This decrease is likely due simply to the fact that the typical, most widely used, method of smbg involves obtaining blood samples from a finger stick. Another difficulty is due to the various calculations surrounding the prospective administration of insulin taken a meal, where those calculations are based upon the concept of determining the amount of carbohydrate in a meal and, as an adjunct of the meal, subcutaneously injecting oneself with an insulin dose to counteract the prospective insulin deficiency.
Currently, xe2x80x9ccarbohydrate countingxe2x80x9d is used in conjunction with a glucose level measurement to determine an appropriate insulin dosage to be taken with the meal. A physician provides the patient with a set of calculations or tables to allow self-determination of that insulin dosage. The calculations and tables are based on a wide variety of factors, including, e.g., body weight and sensitivity of the individual to insulin.
My invention is a simple, circular slide rule tailored for (or selected by the physician for) a specific patient depending upon the medical condition and physical makeup of the patient.
Other calculators have been used in the healthcare field. For instance, U.S. Pat. No. 4,308,450 shows a two-piece slide calculator for determining metabolic requirements and parenteral feeding dosages.
U.S. Pat. No. 4,149,068 shows a circular slide rule improvement which is said to be used in particular for use in X-ray dosage calculations.
A two-part linear slide rule has, on occasion, been provided by the Children""s Hospital of Los Angeles to its patients for determination of insulin dosage.
None of the cited documents shows a circular calculator for the purpose of my invention nor does any have the information described herein.
Other circular calculators are used for a variety of reasons ranging from calculating the odds in horse races (U.S. Pat. No. 4,001,551, to Hirsimaki) to determining appropriate times for planting, growing, and harvesting of crops (U.S. Pat. No. 5,273,320, to deMaCarty).
This invention is a manual circular calculator for determining a specific insulin injection dosage to be taken with a meal. It is made up of a a first circular member having a center, a radius, and a viewing panel (pie-shaped or wedge-shaped) extending from the center. Preferably, a series of patient-measured blood glucose levels is found along a radius adjacent that viewing panel. The viewing panel may be an open window-like area or a transparent material such as a polymer. The calculator also includes a second circular member similarly having a center and a radius larger than the radius of the first circular member. A number of insulin injection dosage value arrays, each array having a number of insulin injection dosage values, are positioned on the second or back circular member in an area and position such that the values are visible in the viewing panel those values correspond to the measured blood glucose levels on adjacent the viewing panel. The displayed insulin injection dosage values further correspond to an ingested carbohydrate amount positioned on the exterior periphery of the first circular member.
The centers of the first circular member and the second circular member coincide. The two discs are rotatable about those centers with respect to each other and allow the display of an array of insulin injection dosage values in the viewing panel that both corresponds to an ingested carbohydrate amount and to measured blood glucose levels.
The insulin injection dosage value arrays may be selected from arrays found in the included Tables. The individual values generally are 0-40 units, but may be from 0-3 units.
Since this calculator is desirably used by children, it may be decorated with, e.g., a foodstuff, pictured thereon. However, the pictured foodstuff may corresponds to the insulin sensitivity of a patient and be used to distinguish one calculator from another calculator.
The invention includes sets of calculators wherein at least some of said calculators have differing arrays of insulin injection dosage value arrays, perhaps with values selected from the Tables included herein.
Finally, the invention includes a method of using the calculator for determining an insulin injection dosage to be taken with a meal using the invemtive manual circular calculator, comprising the steps of
a.) aligning the first circular member by rotation with respect to the second circular member so that a chosen ingested carbohydrate amount (found on the back disc""s periphery) is adjacent the viewing panel so that an insulin injection dosage value array is visible in that viewing panel,
b.) selecting a measured blood glucose level from those found adjacent the viewing panel, and
c.) determining a corresponding insulin injection dosage value adjacent the selected measured blood glucose level.
The inventive method further includes the step of selecting an appropriate variation of the inventive manual circular calculator for a patient, as would be done by a physician, desirably from the noted set.